Iatrogenic keratectasia after laser in situ keratomileusis for less than-4.0 to-7.0 diopters of myopia

Purpose: To study 13 eyes with less than -4.0 to -7.0 diopters of myopia th at developed central or inferior keratectasia after laser in situ keratomil eusis (LASIK). Methods: The progress of the ectasia was determined by a series of pre- and post-LASIK topographies and the case histories. Results: Progressive ectasia developed from 1 week to 27 months after LASIK . This necessitated the wearing of hard contact lenses or penetrating kerat oplasty. One eye improved for some months after photorefractive keratectomy retreatment. Two eyes in 1 patient and 1 eye in a second patient had laten t keratoconus before surgery. Conclusion: Laser in situ keratomileusis can cause permanent weakening and ectasia of the cornea even in eyes with low myopia. J Cataract Refract Surg 2000; 26:967-977 (C) 2000 ASCRS and ESCRS.